The present invention falls within a family of inventions by the inventor such as those described in U.S. Pat. No. 6,554,596 entitled “FLUID TURBINE DEVICE” issued Apr. 29, 2003 and U.S. patent application Ser. No. 10/680,236, entitled “ROTARY PISTONS”. These inventions essentially relate to rotary pistons, motors and pumps in the nature having encased rotors with radially extending vanes which move in and out of the rotors, depending on their location within the casing. The vane movement in and out of the rotor is achieved by cam surfaces within the casing. The walls of the casing are not of uniform radius, and are formed so as to facilitate movement of the vanes and flow of fluid between inlet and outlet ports in the casing.
There has been a need to develop a pump which is stronger than conventional pumps, and which can be used in applications for moving heavy fluids or fluids with solids in them.
It is an object of the present invention to provide an improved pump for such applications.